Process and apparatus for adjusting the length and/or tension of a rope



Sept. 4, 1962 R. DARDY 3,052,320

PROCESS AND APPARATUS FOR ADJUSTING THE LENGTH AND/OR TENSION OF A ROPE Filed May 16, 1960 f Lm wlL 7 Z A 7 3 asel ml w- 7 W 6 fiwfi Z 5 IN V EN TOR.

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This invention relates to processes and apparatus for tensioning cables or ropes and has more particular refer ence to such processes and apparatus when employed to tension cables or ropes employed in winding units in mine shafts or the like.

In mine shaft equipment employing multi-rope winding units it is necessary to mount on each rope a special device to equalize the tension of the various ropes. When a single rope winding system is used, as in the Koepe pulley winding system, a conveyance such as a skip or cage is often mounted on each run of the rope and, in such case, it is necessary that when a unit has reached the top landing the other unit be exactly placed at the bottom landing. However, in such a system, particularly at the beginning of the operation, it is normal for the rope to lengthen itself so that the positions of the conveyances when they stop do not agree any more with the landings and it then becomes necessary to compensate for the lengthening of the rope of the suspension gear.

Tensioning devices known to date do not at the same time provide for the equalization of the various rope tensioning in multi-rope installations and for compensation for lengthening of the rope in the single rope installation.

For the multiple installation the tensioning devices generally include a dynamometer for calculating the tension of each rope and a mechanical device for adjusting the length of the rope. In each of the rope suspension gears to be supervised, either the whole or part of the measuring unit is interposed, which leads to the use of measuring units having rigorously identical characteristics in order to obtain accurate measuring. These characteristics are correct, of course, when first made by the manufacturer, but some of the time, after use, such characteristics become different with the passage of time for the various units.

The mechanical devices provided to adjust the rope tensioning are generally angle devices. The equalization of the tensions is effected by trail and error and the operation takes a much longer time as it is necessary to support the skip or cage in order to displace the angles. When the angles are mounted the skip or cage must be released and the new tensions obtained must be verified to see that they are as desired; otherwise, the operation must be gone through once more.

In the case of the Koepe pulley type installation employing a single rope having a skip on each run, the takeup of the rope lengthening is effected as for the equalization of the tensioning in the multi-rope installation, by trial and error. Both units must be supported, then the lengthening must be mechanically taken up, for example, with angles, then the units must be released in order to verify the rope length and eventually resume the operation until the conformity of the landings is obtained. Also, the use of dynamometers also produces parasite vibrations during stops and start-ups of the skips or cages.

It has been proposed to employ a hydraulic device for automatically regulating the rope tensioning. Such device includes a cylinder on each suspension gear with the cylinders being coupled with each other by pipes. This device appears satisfactory in so far as its principle is concerned but presents practically a rather serious drawback. The liquid always being under pressure, risks of leakage rates atent inc at the joints and rupture of the pipes makes this operation risky.

One of the objects of the present invention is to provide a novel and improved process and apparatus for regulating the tension and/or the lengthening of ropes which overcome the above defects.

Another object of the present invention .is to provide novel apparatus for regulating the tension of the ropes, or, in the case of a single rope employing a Koepe pulley type winding system, to regulate the rope length without requiring the conveyances to be supported.

Another object of the present invention :is to provide apparatus as characterized above, including a hydraulic cylinder and piston assembly for each rope, and means for clamping such assembly to the ropes.

A further object of the invention is to provide a novel and improved process for regulating the tension and/ or length of ropes which is economical and efficient and apparatus which is simple and inexpensive in construction, etlicient in operation, and one which eliminates the possibility of leakage during operation.

Other objects and advantages of the invention will appear in the following description when considered in connection with the accompanying drawings, in which:

PEG. 1 is a diagrammatic side elevational view of one embodiment of the apparatus for adjusting the tension and/ or the length of a rope constructed in accordance with the present invention for carrying out the process thereof;

FIG. 2 is a vertical sectional view taken on the line 2-2 of FIG. 1; and

FIG. 3 is a fragmentary diagrammatic side elevational view of a modified form of the apparatus.

The present invention provides a novel process and apparatus for adjusting the length and/or tension of a rope placed under tension by the weight of a mass and, in general, comprises connecting one end of the rope and the mass by means of a fluid coupling including a member in the form of a cylinder and another member in the form of a piston slidably mounted in the cylinder, with the end of the rope connected to one member and the mass connected to the other member, adjusting the position of the piston in the cylinder by hydraulic means until the desired length and/ or tension of the rope has been obtained, then clamping the piston relative to the cylinder by suitable means and reducing the hydraulic pressure in the cylinder to zero.

The invention is particularly adapted for adjusting the length and/ or tension of ropes employed for hoisting and lowering conveyances such as skips and cages in mine shafts or the like and for purpose of illustration will be described as employed with such apparatus.

Referring now to the drawings, there is diagrammatically illustrated, in FIGS. 1 and 2, a multi-rope winding unit installation for hoisting and lowering conveyances such as skips or cages in mine shafts or the like, with each rope provided with a tensioning and/ or length adjusting device constructed in accordance with the present invention. As there shown, two ropes 1t), 11, each have their respective suspension gears 12, 13, pivotally connected to rope tensioning devices, indicated generally at M, 1.5, which devices are, in turn, pivotally mounted between spaced apart parallel structural beams 16, 16 forming a fixed part of the cage or skip. The rope tensioning and/or lengthening devices 14-, 15 act as hydraulic jacks or couplings for connecting the ropes to the cage or skip.

Each of the hydraulic jacks or couplings 14, 15 are identical in construction and, as shown, each comprises a cylinder 17 having a piston 18 mounted therein. The piston 18 has a piston rod 19 extending upwardly through the top wall of the cylinder 17 and an integral rod 20 extending downwardly through the bottom wall of the cylinder. The rod is threaded and carries a pair of lock nuts 21, 22. The upper ends of the piston rods 19 of the hydraulic couplings are pivotally connected to the suspension gears 12 and 13, respectively, of the ropes 1t and 11. The cylinders 17 are pivotally mounted between the structural beams 16, 16 of the cage or skip by crosshead pins 23, 24.

A piping system, indicated generally at 25, for supplying and withdrawing hydraulic fluid to and from the cylinders 17 is shown as comprising a pipe 26 having a cutofl valve 27 mounted therein and connected at one end to a four-way connection 28 and at its other end to the top part of hydraulic cylinder 17 of hydraulic jack 14. A pipe 29 having a cut-off valve 30 mounted therein and connected at one end to the four-way connection 28 and at its upper end to the top part of hydraulic cylinder 17 of hydraulic jack 15. The upper end portions of pipes 26 and 29 may be made flexible to accommodate any movement of the cylinders to which they are connected. The four-way connection 28 has a gauge 32 connected thereto and a pipe 33 connected to a hand operated hydraulic pump 34. -A cut-otf valve 35 is mounted in the pipe 33 and the pump 34 is provided with a valve 36 to permit fluid to pass from the cylinders 17 through pipe 33 back into the supply tank 37 for the hydraulic pump 34. The upper flexible ends of the pipes 26 and 29 may be fixedly connected to the cylinders 17; preferably, however, and as shown, the ends of the pipes 26 and 29 are detachably connected, as by quick coupling devices 38, to valves 39 mounted on the cylinders.

The manner in which the device is operated to properly adjust the tension on the two ropes connected to the cage or skip is as follows:

To measure the tensioning of rope 10, valves 30 and 35 are closed and valve 27 is opened. The nuts 21, 22 are brought down to the end of the rod 20 of jack 14 to free the cylinder, the liquid pressure in the cylinder is given by gauge 32.

To measure the tension of rope 11, the same procedure is followed, closing valves 27 and 35 and opening valve 30. It is then easy to equalize the tensions in the two ropes by either adding liquid by use of the hand operated pump 34 to increase the pressure in the cylinder where the pressure is lowest or in discharging some liquid in the cylinder when the pressure is highest by opening the valve 36.

When the tensions in the two ropes have been equalized, the nuts 21, 22 are moved into contact with the cylinders 18 for clamping the cylinders. Then the pressure in the system is reduced to zero by opening valves 27, 30 and 35.

The equalization of the tensions of the two ropes may also be obtained more quickly by closing valve 35 and opening valves 27 and 30. The clamping nuts 21, 22 being brought to the ends of the lower piston rods 20, the equilibrium is obtained in the hydraulic system and in the rope tensioning. The clamping nuts are then placed in contact with the cylinders and the pressure in the two cylinders is reduced to zero by opening valve 35.

In the apparatus shown in FIGS. 1 and 2, in each of the hydraulic couplings 14 and 15, the piston clamping is obtained in one direction by threaded rod 20 and lock nuts 21, 22, and in the other direction by the weight of the winding conveyance itself.

In FIG. 3 there is shown a modified form of the device in which the piston clamping is mechanical in both directions. In this particular modification the suspension gear 40 of the rope is pivotally connected to an inverted U-shaped support member 41, between the legs of which the hydraulic jack or coupling member, indicated generally at 42, is pivotally mounted. The hydraulic jack is shown as comprising a hydraulic cylinder 43 having a piston 44 mounted therein. The piston has a piston rod 45 extending upwardly through the top wall of the cylinder and through a cage member 46 in the shape of a stirrup fixedly mounted on the top wall of the cylinder and a rod 4-7 extending downwardly through the bottom wall of the cylinder and pivotally mounted between structural members 48 of a skip or cage. The upper end portion of the piston rod 45 is threaded and lock nuts 49, 50 are mounted thereon on the portion of the piston rod within the cage member 46.

The pipe line 51 of the hydraulic system is connected to the bottom portion of the cylinder in the same manner as are the pipe lines shown in the modification illustrated in FIG. 1. Also, in this modification, as in the modification shown in FIGS. 1 and 2, the pivotal axes connecting the hydraulic jack to the suspension gear of the rope and to the cage or skip extend at right angle to each other.

The operation of the apparatus of this modification is generally similar to the operation of the apparatus shown in FIGS. 1 and 2. However, with the apparatus of this modification, the piston clamping is mechanical in both directions as the lock nut 49 on the piston rod 45 prevents upward movement of the hydraulic jack and the lock nut 56 prevents downward movement thereof after the piston has been adjusted and the nuts tightened against the top wall of the piston and the under side of the top cross piece of the cage member 46.

In the case of single rope installations such as the Koepe pulley winding system, it is suflicient to fit one of the cages with a hydraulic jack to insure the conformity of the landings.

When a rope lengthening has taken place, it is sufiicient to send some liquid under pressure into the cylinder of the device to catch up the lengthening and to afterwards clamp the piston in relation to the cylinder by means of the threaded rod and locking nuts thereon. It is, consequently, unnecessary to support the skip or cage in order to obtain this result and the exact position of the unit appears immediately, which reduces considerably the time of operation.

From the foregoing, it readily will be seen that there has been provided a novel and improved process and apparatus for tensioning and/ or lengthening a rope or ropes, a process which is economical and efiicient; and an apparatus which is simple in construction, inexpensive, and eflicient in operation.

Obviously, the invention is not restricted to the various embodiments thereof herein shown and described.

What is claimed is:

1. A process for adjusting the length of a rope placed under tension by the weight of a mass comprising the steps of connecting one end of the rope and the mass by means of a hydraulic coupling including a member in the form of a cylinder and another member in the form of a piston slidably mounted in the cylinder, with the end of the rope connected to one member and the mass connected to the other member, moving the piston in the cylinder by hydraulic pressure until the desired length of the rope has been reached; clamping the piston in relation to the cylinder; and then reducing the hydraulic pressure to zero.

2. A process for adjusting the tension and the length of a plurality of ropes placed under tension by the weight of a mass comprising the steps of connecting one end of each of the ropes and the mass by means of hydraulic couplings each including a member in the form of a cylinder and another member in the form of a piston slidably mounted in the cylinder, with the end of a rope connected to one member and the mass connected to the other member, moving the pistons in the cylinders by hydraulic pressure until the tension and the length of the ropes have been equalized at the desired length and tension; clamping the pistons within their respective cylinders; and then reducing the hydraulic pressure in each cylinder to zero.

3. Apparatus for adjusting the length of a rope adapted to be placed under longitudinal tension by the weight of a mass, comprising a hydraulic coupling including a member in the form of a cylinder and a member in the form of a piston reciproeatively mounted in said cylinder; means connecting one end of the rope to one of said members; means connecting said mass to the other of said members; means including a conduit for connection to said cylinder to permit the ingress and egress of hydraulic fluid to and from said cylinder on one side of said piston so that said fluid will be under pressure by the Weight of said mass; means for regulating the pressure of the fluid in said cylinder to thereby move the pisston relative to the cylinder and thereby regulate the length of said rope; means for clamping the piston and cylinder together in their adjusted positions; and valve means for reducing the pressure of the fluid in said cylirder to zero after the length of said rope has been adjusted.

4. Apparatus as set forth in claim 3, wherein said means for clamping the piston and cylinder together comprises an integral threaded rod carried by said piston 6 and projecting downwardly through the bottom wal of said cylinder, and locking nuts adjustably mounted on the portion of said rod projecting through the bottom wall of said cylinder.

5. Apparatus as set forth in claim 3, wherein the piston is provided with a piston rod projecting upwardly through the top wall of said cylinder and wherein the end of the rope is pivotally connected to the upper end of said piston rod and said cylinder is pivotally connected to said mass.

6. Apparatus as set forth in claim 5, wherein the pivotal axis of the pivotal connection between said rope and said piston rod extends in a direction perpendicular to the direction in which the pivotal axis of the pivotal con nection between said cylinder and said mass extends.

References Cited in the file of this patent UNITED STATES PATENTS 1,632,083 Kieckhefer lune 14, 1927 

